Netmask is set to 255.255.255.255 after system restore or after connman offline -> onnline mode.
Is it a problem in master as well? otherwise, we probably have to ignore it since it's relate to connman and too late for us to change things for 1.1.2
What host, what network hardware? Also connman 1.3 will be landing very shortly, can you test with that?
The behavior could not be reproduced with Yocto 1.3. I guess this is enough for this bug to be closed.